1 Delivers 15~32dB sound attenuation while maintaining optimal airflow, perfectly balancing ventilation efficiency and noise blocking performance. 2 Constructed with premium materials: Aluminum, Galvanized Steel or SS304. Waterproof and anti-corrosion, built for long-term outdoor service life. 3 Ideal for generator rooms, data centers, HVAC systems, and all types of industrial ventilation openings. 4 Custom size, depth, and color can be produced according to your project drawings and specifications. 5 Free CAD design service and detailed installation guidance are provided to ensure smooth project execution.